If not in a list context, returns the number of fields found and splits into
the @_ array. (In a list context, you can force the split into @_ by
?? as the pattern delimiters, but it still returns the array
value.) The use of implicit split to @_ is deprecated, however.
If EXPR is omitted, splits the $_ string. If PATTERN is also omitted, splits on whitespace (after skipping any leading whitespace). Anything matching PATTERN is taken to be a delimiter separating the fields. (Note that the delimiter may be longer than one character.) If LIMIT is specified and is not negative, splits into no more than that many fields (though it may split into fewer). If LIMIT is unspecified, trailing null fields are stripped (which potential users of pop() would do well to remember). If LIMIT is negative, it is treated as if an arbitrarily large LIMIT had been specified.
A pattern matching the null string (not to be confused with
a null pattern
//, which is just one member of the set of patterns
matching a null string) will split the value of EXPR into separate
characters at each point it matches that way. For example:
produces the output 'h:i:t:h:e:r:e'.
The LIMIT parameter can be used to partially split a line
When assigning to a list, if LIMIT is omitted, Perl supplies a LIMIT one larger than the number of variables in the list, to avoid unnecessary work. For the list above LIMIT would have been 4 by default. In time critical applications it behooves you not to split into more fields than you really need.
If the PATTERN contains parentheses, additional array elements are created from each matching substring in the delimiter.
produces the list value
If you had the entire header of a normal Unix email message in $header, you could split it up into fields and their values this way:
/PATTERN/ may be replaced with an expression to specify
patterns that vary at runtime. (To do runtime compilation only once,
As a special case, specifying a PATTERN of space (
' ') will split on
white space just as split with no arguments does. Thus, split(' ') can
be used to emulate awk's default behavior, whereas
will give you as many null initial fields as there are leading spaces.
A split on /\s+/ is like a split(' ') except that any leading
whitespace produces a null first field. A split with no arguments
really does a
(Note that $shell above will still have a newline on it. See chop , chomp , and join .)